Cartridges for caulking and sealing materials are presently standardized in size and shape, and any change in this would be very expensive. Millions of caulking guns are shaped to accommodate standard size cartridges, and also a substantial capital investment has been made in machinery for handling, filling, and sealing cartridges.
The contents of a cartridge have not been completely dispensible, because a little remains around the front end of the cartridge and in the full volume of the nozzle. The marking of the contents on cartridges ordinarily indicates the total volume placed in the cartridge when initially filled, but not quite all of that volume is available to the user because of the inability to dispense the full volume of the contents. This discrepancy has been noted by interests seeking to protect consumers, and some government regulations now require the cartridge to be marked with the volume of contents actually dispensible. Enlarging the cartridges slightly to accommodate more contents is not a practical way of maintaining the previous total volume marking, because expensive changes would have to be made in machines for filling and sealing the cartridges.
The invention involves recognition of the need for marking standard size cartridges with as large a volume of dispensible contents as possible, and the invention seeks a larger initial volume of contents and more complete dispensing of the contents to make as much of the contents available to the user as possible and to reduce the waste of undispensible contents. The invention also aims to achieve this without requiring substantial changes in machines for filling and sealing cartridges or in guns already in use for dispensing material from cartridges.